I'm planning to sell my 17" rims with 205/40/17 tires to go back to the original stock base steelies (175/65/14 I think?). Does anyone know what improvements in mpg I will get by going back to the base steelies? My 17" wheels are much heavier than the base wheels (by my rough estimate, I would say each wheel weighs at least 10-15 lbs heavier than the stock wheels).
I really want to know how much $$ I'll be saving.

 

I've gone from 14" wheels (enkei 92s) to 15" wheels (slipstreams, OEM alloy, OEM Integra SE) and 17" wheels (RAYS G Games) and I can't say I've seen a noticable difference between them. I have a scangauge II and I monitor my mileage pretty closely, too.

 

it might not affect it that much cause the weight is not sprung weight from the body if you lighten the body itself or shed weight in the car you might see a noticable difference thats intresting i might just look it up to see what the pros say

 

I had upgrade to 17" with 205/40/17 tires and really MPG had change but not so much.I still have the stock wheels.Sometimes i want to install them back to give the car a stock look again but I LOVE how the car looks with the Tenzo-R.If anybody start doing mods to the factory set up this include wheels upgrade and dropping the car with lower springs MPG will change in some way for sure.But the point is that you will LOVE the new look that you can give to your car....I will stay with the 17".If you like make a poll to see what members in FF think about it.Good luck with your final decision.If you can upload a picture of your ride to see how the wheels looks in your car.Take care my friend.

 

What are the 17" wheels you have?

For me, I'd rather have a 17" wheel than a 14" steelie. Not so much because of weight, but more because of it's handling characteristics. A wider, stickier tire would help in most situations and weather conditions. Also a shorter, stiffer sidewall will flex less than a taller sidewall, which should help cornering. Not to mention a 17" wheel would look better than a steelie. You could always compromise and go 16".

 

The biggest problem with upgrading in wheel size isn't the actual diameter but instead the width of the wheel and the weight. The larger width has more contact with the ground creating more friction (better grip, lower mpg) and the heavier rim creates a larger moment of inertia so it takes more power to get the car moving.